From: "Martin K. Petersen" <martin.petersen@oracle.com>
To: Damien Le Moal <damien.lemoal@wdc.com>
Cc: linux-block@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
linux-scsi@vger.kernel.org,
"Martin K . Petersen" <martin.petersen@oracle.com>,
dm-devel@redhat.com, Mike Snitzer <snitzer@redhat.com>,
Christoph Hellwig <hch@lst.de>,
Matias Bjorling <matias.bjorling@wdc.com>
Subject: Re: [PATCH v4 02/11] scsi: sd_zbc: Reduce boot device scan and revalidate time
Date: Tue, 16 Oct 2018 00:50:21 -0400 [thread overview]
Message-ID: <yq14ldmv6k2.fsf@oracle.com> (raw)
In-Reply-To: <20181012100850.23316-3-damien.lemoal@wdc.com> (Damien Le Moal's message of "Fri, 12 Oct 2018 19:08:41 +0900")
Damien,
> Handling checks of ZBC device capacity using the max_lba field of the
> REPORT ZONES command reply for disks with rc_basis == 0 can be done
> using the same report zones command reply used to check the "same"
> field.
>
> Avoid executing a report zones command solely to check the disk capacity
> by merging sd_zbc_check_capacity() into sd_zbc_check_zone_size() and
> renaming that function to sd_zbc_check_zones(). This removes a costly
> execution of a full report zones command and so reduces device scan
> duration at boot time as well as the duration of disk revalidate calls.
>
> Furthermore, setting the partial report bit in the REPORT ZONES command
> cdb can significantly reduce this command execution time as the device
> does not have to count and report the total number of zones that could
> be reported assuming a large enough reply buffer. A non-partial zone
> report is necessary only for the first execution of report zones used to
> check the same field value (to ensure that this value applies to all
> zones of the disk). All other calls to sd_zbc_report_zones() can use a
> partial report to reduce execution time.
>
> Using a 14 TB ZBC disk, these simple changes reduce device scan time at
> boot from about 3.5s down to about 900ms. Disk revalidate times are also
> reduced from about 450ms down to 230ms.
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
--
Martin K. Petersen Oracle Linux Engineering
WARNING: multiple messages have this Message-ID (diff)
From: "Martin K. Petersen" <martin.petersen@oracle.com>
To: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Jens Axboe <axboe@kernel.dk>,
"Martin K . Petersen" <martin.petersen@oracle.com>,
Mike Snitzer <snitzer@redhat.com>,
linux-block@vger.kernel.org, dm-devel@redhat.com,
linux-scsi@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
Matias Bjorling <matias.bjorling@wdc.com>
Subject: Re: [PATCH v4 02/11] scsi: sd_zbc: Reduce boot device scan and revalidate time
Date: Tue, 16 Oct 2018 00:50:21 -0400 [thread overview]
Message-ID: <yq14ldmv6k2.fsf@oracle.com> (raw)
In-Reply-To: <20181012100850.23316-3-damien.lemoal@wdc.com> (Damien Le Moal's message of "Fri, 12 Oct 2018 19:08:41 +0900")
Damien,
> Handling checks of ZBC device capacity using the max_lba field of the
> REPORT ZONES command reply for disks with rc_basis == 0 can be done
> using the same report zones command reply used to check the "same"
> field.
>
> Avoid executing a report zones command solely to check the disk capacity
> by merging sd_zbc_check_capacity() into sd_zbc_check_zone_size() and
> renaming that function to sd_zbc_check_zones(). This removes a costly
> execution of a full report zones command and so reduces device scan
> duration at boot time as well as the duration of disk revalidate calls.
>
> Furthermore, setting the partial report bit in the REPORT ZONES command
> cdb can significantly reduce this command execution time as the device
> does not have to count and report the total number of zones that could
> be reported assuming a large enough reply buffer. A non-partial zone
> report is necessary only for the first execution of report zones used to
> check the same field value (to ensure that this value applies to all
> zones of the disk). All other calls to sd_zbc_report_zones() can use a
> partial report to reduce execution time.
>
> Using a 14 TB ZBC disk, these simple changes reduce device scan time at
> boot from about 3.5s down to about 900ms. Disk revalidate times are also
> reduced from about 450ms down to 230ms.
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
--
Martin K. Petersen Oracle Linux Engineering
next prev parent reply other threads:[~2018-10-16 4:50 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-12 10:08 [PATCH v4 00/11] Zoned block device support improvements Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 01/11] scsi: sd_zbc: Rearrange code Damien Le Moal
2018-10-16 4:48 ` Martin K. Petersen
2018-10-16 4:48 ` Martin K. Petersen
2018-10-12 10:08 ` [PATCH v4 02/11] scsi: sd_zbc: Reduce boot device scan and revalidate time Damien Le Moal
2018-10-16 4:50 ` Martin K. Petersen [this message]
2018-10-16 4:50 ` Martin K. Petersen
2018-10-12 10:08 ` [PATCH v4 03/11] scsi: sd_zbc: Fix sd_zbc_check_zones() error checks Damien Le Moal
2018-10-12 10:23 ` Hannes Reinecke
2018-10-12 10:23 ` Hannes Reinecke
2018-10-12 11:41 ` Damien Le Moal
2018-10-12 11:41 ` Damien Le Moal
2018-10-16 4:51 ` Martin K. Petersen
2018-10-16 4:51 ` Martin K. Petersen
2018-10-17 7:21 ` Christoph Hellwig
2018-10-17 7:21 ` Christoph Hellwig
2018-10-12 10:08 ` [PATCH v4 04/11] block: Introduce blkdev_nr_zones() helper Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 05/11] block: Limit allocation of zone descriptors for report zones Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 06/11] block: Introduce BLKGETZONESZ ioctl Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 07/11] block: Introduce BLKGETNRZONES ioctl Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 08/11] block: Improve zone reset execution Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 09/11] block: Expose queue nr_zones in sysfs Damien Le Moal
2018-10-12 10:08 ` [PATCH v4 10/11] block: add a report_zones method Damien Le Moal
2018-10-16 4:55 ` Martin K. Petersen
2018-10-16 4:55 ` Martin K. Petersen
2018-10-16 15:17 ` Mike Snitzer
2018-10-16 15:17 ` Mike Snitzer
2018-10-12 10:08 ` [PATCH v4 11/11] block: Introduce blk_revalidate_disk_zones() Damien Le Moal
2018-10-16 5:00 ` Martin K. Petersen
2018-10-16 5:00 ` Martin K. Petersen
2018-10-16 15:17 ` Mike Snitzer
2018-10-16 15:17 ` Mike Snitzer
2018-10-13 22:43 ` [PATCH v4 00/11] Zoned block device support improvements Jens Axboe
2018-10-15 0:45 ` Damien Le Moal
2018-10-15 0:45 ` Damien Le Moal
2018-10-16 2:34 ` Jens Axboe
2018-10-16 3:43 ` Damien Le Moal
2018-10-16 3:43 ` Damien Le Moal
2018-10-18 7:57 ` Damien Le Moal
2018-10-18 7:57 ` Damien Le Moal
2018-10-23 15:59 ` Jens Axboe
2018-10-24 2:26 ` Martin K. Petersen
2018-10-24 2:26 ` Martin K. Petersen
2018-10-24 15:03 ` Mike Snitzer
2018-10-24 15:03 ` Mike Snitzer
2018-10-24 15:37 ` Martin K. Petersen
2018-10-24 15:37 ` Martin K. Petersen
2018-10-24 16:04 ` Bart Van Assche
2018-10-24 16:04 ` Bart Van Assche
2018-10-25 14:30 ` Jens Axboe
2018-10-25 14:30 ` Jens Axboe
2018-10-24 8:04 ` Damien Le Moal
2018-10-24 8:04 ` Damien Le Moal
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